QuestionQUESTION: ok I am having a little trouble recognizing the date of my conception. I normally get my period for 6-7 days and it would come every 28 days. on march 17 i got my period but it lasted for about 4 days. i had sex the 22nd and 23rd with my boyfriend. Then on April 2nd I had unprotected sex with my ex boyfriend. My period came again exactly 28 days on April 13 but it was very irregular. Then I went and got a sonogram may 1st and it said I was 6 weeks. I had another sonogram June 11th and the doctor said i was exactly 12 weeks and 4 days. But when i count back, I didn't have sex with nobody in those days so please help me! When did I conceive?
ANSWER: By convention, a pregnancy is dated as two weeks on the date of conception. So if an ultrasound dated you as six weeks on May 1, that means you count back four weeks to find the date of conception, April 3. Since sperm can survive up to five days, that means that the encounter you had on April 2 is most likely when you got pregnant. The bleeding you experienced on April 13 was implantation bleeding, which is caused by the embryo burrowing into the uterine wall and is not uncommon.
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QUESTION: But what about when I got the sonogram results on June 11th. When you count back 2 weeks that puts me in the position where my boyfriends sperm could have survived...
AnswerEven using the results from June 11th, your conception date would then be March 29. This is still too far away (6 days) from the last date you were with your boyfriend. Besides that, the May 1 results will be more accurate for dating the pregnancy; any ultrasound performed after 10 weeks of pregnancy has a degree of uncertainty for dating.
